The University of Southampton
University of Southampton Institutional Repository

PSR J0030+0451 mass and radius from NICER data and implications for the properties of neutron star matter

Miller, Cole, Lamb, Frederick K., Dittmann, A. J., Bogdanov, Slavko, Arzoumanian, Zaven, Gendreau, Keith C., Harding, Alice K., Ho, Wynn C.G., Lattimer, James M., Ludlam, Renee M., Mahmoodifar, Simin, Morsink, Sharon, Ray, Paul S., Riley, Thomas E., Wood, Kent S., Enoto, T., Foster, R., Okajima, T., Prigozhin, Gregory Y. and Soong, Y. (2019) PSR J0030+0451 mass and radius from NICER data and implications for the properties of neutron star matter. Astrophysical Journal Letters, 887 (1), [L24].

Record type: Article

Abstract

Neutron stars are not only of astrophysical interest, but are also of great interest to nuclear physicists because their attributes can be used to determine the properties of the dense matter in their cores. One of the most informative approaches for determining the equation of state (EoS) of this dense matter is to measure both a star's equatorial circumferential radius R e and its gravitational mass M. Here we report estimates of the mass and radius of the isolated 205.53 Hz millisecond pulsar PSR J0030+0451 obtained using a Bayesian inference approach to analyze its energy-dependent thermal X-ray waveform, which was observed using the Neutron Star Interior Composition Explorer (NICER). This approach is thought to be less subject to systematic errors than other approaches for estimating neutron star radii. We explored a variety of emission patterns on the stellar surface. Our best-fit model has three oval, uniform-temperature emitting spots and provides an excellent description of the pulse waveform observed using NICER. The radius and mass estimates given by this model are ${R}_{e}={13.02}_{-1.06}^{+1.24}$ km and $M={1.44}_{-0.14}^{+0.15}\,{M}_{\odot }$ (68%). The independent analysis reported in the companion paper by Riley et al. explores different emitting spot models, but finds spot shapes and locations and estimates of R e and M that are consistent with those found in this work. We show that our measurements of R e and M for PSR J0030+0451 improve the astrophysical constraints on the EoS of cold, catalyzed matter above nuclear saturation density.

Text
1912.05705 - Accepted Manuscript

Accepted/In Press date: 24 October 2019
Published date: 12 December 2019

Identifiers

Local EPrints ID: 436752
URI: http://eprints.soton.ac.uk/id/eprint/436752
ISSN: 2041-8205
PURE UUID: 39419cff-4777-449c-8495-a38cc4a5ec7d
ORCID for Wynn C.G. Ho: orcid.org/0000-0002-6089-6836

Catalogue record

Date deposited: 03 Jan 2020 17:30

Contributors

Author: Cole Miller
Author: Frederick K. Lamb
Author: A. J. Dittmann
Author: Slavko Bogdanov
Author: Zaven Arzoumanian
Author: Keith C. Gendreau
Author: Alice K. Harding
Author: Wynn C.G. Ho
Author: James M. Lattimer
Author: Renee M. Ludlam
Author: Simin Mahmoodifar
Author: Sharon Morsink
Author: Paul S. Ray
Author: Thomas E. Riley
Author: Kent S. Wood
Author: T. Enoto
Author: R. Foster
Author: T. Okajima
Author: Gregory Y. Prigozhin
Author: Y. Soong